Mikako Satsukitane

Mikako is an upperclassman to Tomoki and Mitsuki  and the president of the Student Council. She is Eishiro's childhood friend, whom she refers to as "Ei-kun", and the heiress of a Yakuza family. She is manipulative, a genuis intelectual, cunning, highly intelligent and sadistic, usually towards Tomoki. In the manga, she is forced to take supplementary lessons due to "failing in morals". She also is equal to Sugata in terms of combat abilities. However, Nymph states that she has a grip power of 400kg, which serves to indicate she has a great degree of strength, especially for a normal human. She is the chief mastermind of many schemes in the manga, and Sugata normally enlists the help of Tomoki (and occasionally some others) by persuading him to totally shut down her plans. Many of her schemes are directed to Tomoki, serving to put him in undesirable situations and humiliating him, which suggests she sees him as a toy for her personal entertainment.

Relationships
Tomoki Sakurai

Mitsuki Sohara

Ikaros

Eishiro Sugata- a childhood friend of hers